CHICONAUTLA, Mexico _ All is dark in the overcrowded cell, save for the dim light flickering from a three-tiered bunk bed.
Humbertus Perez writes every night, his flashlight wrapped in cardboard so as not to disturb the accused car thief and the mugger with whom he shares a thin mattress.
The young men snore and occasionally throw a foot in Perez's face, but it's better than sleeping on the floor. There, dozens of inmates _ alleged murderers, rapists, career criminals _ lie sprawled on cots and planks, a malodorous tangle of arms and legs.
Perez, a 54-year-old academic, was Mexico's leading homeowner activist _ a fiery orator who railed against the Mexican housing developers and foreign investors who reaped enormous profits at the expense of working-class people.
To his supporters, he was an incorruptible one-man force. He saved thousands of homeowners from eviction. He led rowdy marches, battled Wall Street investment banks, called judges stubborn mules and publicly shamed governors and presidents _ labeling the entire Mexican political system a criminal enterprise.
Scribbling legal briefs and letters every night while his fellow inmates sleep, Perez tries to keep his campaign alive from Chiconautla prison, 20 miles northeast of Mexico City.
Two years behind bars have taken a toll. Rashes cover his body. Chronic diarrhea has forced him into diapers. He goes days without sleep.
"This is a hard place to do time," Perez said by phone from the mess hall, where fellow inmates guard him so he won't get stabbed. "I thought long ago they would kill me, but God has been very kind."
Outside the prison walls, his homeowner movement, the Mexican Front in Defense of a Dignified Home _ once thousands strong _ is adrift without him.
Perez was arrested on Nov. 4, 2015, as he left a news conference where, in a characteristic burst of barbed oratory, he had accused top government officials of conspiring to destroy his movement. Authorities charged him with robbing two neighbors at gunpoint of a cellphone, a laptop and paint buckets because they owed membership dues to his Mexican Front.
Three sets of judges threw out the charges and ordered Perez's immediate release, saying the witnesses' testimony seemed scripted and contradictory. But the Mexico state attorney general's office persuaded other judges to keep Perez behind bars without bail.
Supporters of Perez say the relentless prosecution of a professor in a country where 95 percent of homicides go unsolved smacks of brutish retaliation.
In Perez's saga, many of the nation's entrenched problems converge: brazen corruption, official impunity and a rigged justice system that crushes those who raise a voice against powerful interests.
Perez's only crime, as his supporters see it: calling out the greed that betrayed the homeownership dreams of millions of Mexicans.
"It's pure revenge of businessmen and politicians," said Arturo Chavarria, president of the College of Architects and Urban Planners, a professional association based in Mexico state. "Perez exposed all the corruption in the affordable housing market and government housing policies over the past 20 years."
